Maximum estimated rainfall is about a quarter-inch in Palm Springs and about one-tenth of an inch in Thermal, she said.

"Overall, we’re not expecting too much rain," Oswant said.

The south-moving storm will begin dousing the region late Friday or early Saturday and continue through Saturday evening, according to the National Weather Service.

The weather service said the Coachella Valley could see about two-tenths of an inch of rain, which the Riverside metropolitan area and Lake Elsinore are expected to get
up to a half-inch of rainfall over the weekend and four-tenths of an
inch will fall in the San Gorgonio Pass near Banning.

The storm reaching the region Friday night could dump snow in some parts of the Riverside and San Bernardino county mountains, though it is still too early to tell whether flooding might occur, particularly in areas scarred by last summer's fires, forecasters said.

The weather service also issued a winter weather advisory for the San Bernardino County Mountains set to expire at 6 p.m. Saturday, with snow levels expected to drop to 5,500 feet.

The storm system will move east out of the region by Sunday, but a separate system expected to bring multiple rounds of significant rain could sweep into the region beginning Monday or Tuesday, according to the weather service.

When precipitation is expected to result in storm-related hazards, the county's Emergency Management Department may issue voluntary evacuation orders. The agency posts mandatory orders when threats are confirmed.

Material from City News Service was used in this report.

Shane Newell covers breaking news and the western Coachella Valley cities of Palm Springs, Cathedral City and Desert Hot Springs. He can be reached at Shane.Newell@DesertSun.com, (760) 778-4649 or on Twitter at @journoshane